FireFly Battery Long Term Users - Speakup

[sailorboy1]

I have had my Firefly house battery bank for 1.5 years now with no problems.

But I would like to read long term users stories (yes I know there aren't a lot that would be on the forum). Especially ones who have had them 5+ years AND spent long (months) periods of not pugging into shore power.

Speak up with your story.

[Training Wheels]

We’ve had ours for over 4 years, 3 g31’s. We don’t have a shore power cord of 110V charger onboard, so never connected to shore power. Full time live aboard cruisers. I pretty much ignore the batteries and they still seem to be working great.

[smac999]

seen a lot of failures. quality control went way down hill I think.

and by failures I mean batteries testing to have ~20ah instead of 116ah a year later

[sogin]

Originally Posted by sailorboy1

I have had my Firefly house battery bank for 1.5 years now with no problems.

But I would like to read long term users stories (yes I know there aren't a lot that would be on the forum). Especially ones who have had them 5+ years AND spent long (months) periods of not pugging into shore power.

Speak up with your story.

Our firefly batteries are 4 years old - we have had zero problems but that might be attributable to our having shore power several times each month.
During winder months we disconnect batteries and at most their voltage drops by 0.2 volts over 6 months period.

[Peeew]

I’ve been using my bank of 5 G31 firefly batteries for three years. I don’t often use shore power. Now on my third 3-4 month trip on the boat. I’m happy with the performance. With more solar I wouldn’t really ever pay much attention to them. My current electrical usage is fairly heavy and it’s winter with short days and imperfect sun angles. After a few gray days at anchor I need to start my generator for an hour or so. Usually I move around a lot and use a little bit of motor time which tops up the batteries once in a while. While I could use more solar etc I don’t have to worry about hurting the batteries with PSOC time. So charging is not a big concern as far as injuring the battery bank used to be.

[sailorboy1]

Originally Posted by smac999

seen a lot of failures. quality control went way down hill I think.

and by failures I mean batteries testing to have ~20ah instead of 116ah a year later

Well without details far as usefulness this is right up there with rumors. That is why i asked for USER feedback so questions of use can be asked.

[smac999]

Originally Posted by sailorboy1

Well without details far as usefulness this is right up there with rumors. That is why i asked for USER feedback so questions of use can be asked.

I've see 100's of bad ones, tested with a $1000 c20 ah meter (same one maine sail uses). not rumors.

all are 99% of time connected shore power boats. it's possible the float is killing them.

I'm not even sure ocean planet sells them anymore. because they are seeing the same issues.

[mlydon]

Smac - that sounds pretty major - are you in the business? Have you spoken to them regarding warranties and such?

Matt

[sailorboy1]

Originally Posted by smac999

all are 99% of time connected shore power boats. it's possible the float is killing them.

Well that is 100% the opposite of the thread question and the manual says to not leave of float. The same thing happens to lithium batteries if you just leave fully charged and on float, they lose their capacity.

So this is NOT the topic.

[Dave Lochner]

Originally Posted by smac999

I've see 100's of bad ones, tested with a $1000 c20 ah meter (same one maine sail uses). not rumors.

all are 99% of time connected shore power boats. it's possible the float is killing them.

I'm not even sure ocean planet sells them anymore. because they are seeing the same issues.

When Firefly batteries appear to have lost capacity, they need to be deeply discharged and recharged at a high current rate (.4C) and then discharged again and recharged at a high current rate. This will restore capacity. See link below.

Ocean Planet Energy still sells Firefly batteries. In a recent conversation with one of their techs, he suggested frequent deep discharges and high current levels for recharging. The manual indicates that .4C is the correct charge level and the batteries can take .5C.

https://www.practical-sailor.com/sys...rine-batteries

[CarinaPDX]

Wow. I bought new G31 batteries (3 of them) almost a year ago, and at that time I did not find a Users Manual. There is one now available, dated May 2021. If I had read that at the time I would have bought gels instead. Everything I read up to the time of purchase indicated that these are robust batteries; the Users Manual tells a different story. A high current (minimum 24A, preferred 48A, per G31 battery) is needed to "restore" the battery, at least once every 30 days, and from a low state of charge - not something I am doing now. The current required to do this is too much for any reasonable battery charger, solar array, or wind generator to supply - only the alternator can supply that much current. And since I am not actively cruising, the batteries are not seeing that sort of charge current. I hope this does not end badly...

Greg

[Dave Lochner]

Originally Posted by CarinaPDX

Wow. I bought new G31 batteries (3 of them) almost a year ago, and at that time I did not find a Users Manual. There is one now available, dated May 2021. If I had read that at the time I would have bought gels instead. Everything I read up to the time of purchase indicated that these are robust batteries; the Users Manual tells a different story. A high current (minimum 24A, preferred 48A, per G31 battery) is needed to "restore" the battery, at least once every 30 days, and from a low state of charge - not something I am doing now. The current required to do this is too much for any reasonable battery charger, solar array, or wind generator to supply - only the alternator can supply that much current. And since I am not actively cruising, the batteries are not seeing that sort of charge current. I hope this does not end badly...

Greg

One big advantage of Firefly is their ability to tolerate long periods at a PSOC, something other LA batteries, especially AGMs, can not do. Somewhere online, maybe the Ocean Planet Energy site, there is an article by Nigel Calder on a FF battery he left for a year at a low PSOC. After a couple of charge discharge cycles the battery had regained its initial capacity.

The batteries can be disconnected and recharged individually. This would only require a 40 or 50 amp charger. Not the best solution, but it would work.

[Bravo46]

Originally Posted by sailorboy1

I have had my Firefly house battery bank for 1.5 years now with no problems.

But I would like to read long term users stories (yes I know there aren't a lot that would be on the forum). Especially ones who have had them 5+ years AND spent long (months) periods of not pugging into shore power.

Speak up with your story.

We’ve had six G31s for four or five years combined with solar all provided by Ocean Planet. We don’t carry a shore power cord. The freezer and refrigerator are fully provisioned in May and stays that way until we haul in October. We also did a winter in the eastern Caribbean.

Couldn’t be more pleased with the Fireflies. If we have several days of rain, a bit of engine time is needed, but who doesn’t motor once in a while. Prior to this my AGMs would give up after about two seasons.

[mjgill1]

This is from the manual.

“Periodic Fast & Complete Charge Cycle Recommendations: Note that periodic fast (high current) charging from a low state of charge can help restore usable capacity after periods of repeated slow charging (less than 0.2C) or deep discharge cycles. It is recommended that the battery goes through a complete charge cycle from a low state of charge every week if they are being heavily cycled or at minimum every 30 days. Ideally the batteries will be charged at a current of 0.4C (46 Amps for an Oasis G31) but a minimum of 0.2C (25A per G31 battery) is acceptable. These charge cycles should end with a 24 hour float charge at 13.5V for the G31 and 4.5V for the 4V 950Ah model. For applications lacking fast charging capability, contact OPE or for alternative restoration procedures.”

[sailorboy1]

Just for the record:

In the 1.5 years I have had my FFI have NEVER done the recovery procedure. I have charged them with every source I have a couple of times, battery charger+alternator+solar, and even at 65% state of charge they would only accept 0.28C. They certainly aren't getting floated much and I now it has currently 2.5 months since they stayed at float. Evan when I have shore power I turn off the battery charger and go back to solar most of the time and the boat DC loads run off the batteries+solar.

Franky if people have experiencing FF batteries drying at the dock why did they even get FF batteries? The only reason the spend the money is for the PSOC protection and what do you need that for if you are going to plug in all/most of the time?